Two-temperature refrigerator



Jan. 13, 1948.

TWO-TEMPERATURE REFRIGERATOR G. K. |WASH!TA Filed July 9, 1943 5 Sheets-Sheet 1 Jan. 13, 1948. G. K. IW-ASHITA 2,434,361

TWO-TEMPERATURE REFRIGERATOR Filed July 9, 1943 5 Sheets-Sheet 2 Jan. 13, 1948. G. K. IWASHITA TWO-TEMRERATURE REFRIGEPATOR Filed July 9, 1943 5 Sheets-Sheet 3 Jan. 13, 1948. e. K. IWASHITA 2,434,361

TWO-TEMPERATURE REFRIGERATOR Filed July 9, 1943 5 Sheets-Sheet 4 jam 1948. G. K. IWASHITA 2,434,361

I TWO-TEMRERATURE REFRIGERATOR Fil y 1943 5 Sheets-Sheet s Patented Jan. 13, 1948 TWO-TEMPERATURE REFRIGERATOR George K. Iwashita, Indianapolis, Ind., assignor, by mesne assignments, to Admiral Corporation, Chicago, 111., a corporation of Delaware Application July 9, 1943, Serial No. 493,993 11 Claims. (01. 62-116) This invention relates to refrigerators, particularly of the type having a single storage compartment maintained at a temperature below freezing.

An object of the invention is to simplify the servicing of a refrigerator of this type.

A further object of the invention is to provide an improved primary-secondary refrigerating system having a hermetically sealed primary circuit which can be easily placed in position and which may be removed without being disrupted.

A still further object of the invention is to provide an improved primary-secondary refrigerating system which may be disassembled for servicing without disturbing the insulation or sealing of the cold chamber from ambient thermal conditions.

A further object of the invention is to provide an improved refrigerator having a particularly effective cooling means which is also adapted to be easily handled in servicing.

A further object of the invention is to provide 2 a refrigerator of the instant type having improved means for causing fast-freezing of foods. A still further object of the invention is to simplify the construction of a refrigerator of the instant type.

Other objects and advantages will become apparent during the description, reference being had to the drawings, wherein:

Fig. 1 is a vertical section showing the structure of a refrigerator which incorporates my invention;

Fig. 2 is an end view of the same refrigerator showing particularly the tubing of the primary refrigerant circulating system;

' Fig. 31s a section taken on the line 33 of Fig. 1;

Fig. 4 is a perspective view showing particularly the opening in the refrigerator top through which the conduits of the primary refrigerating system enters the interior of the cold storage compartment;

refrigerator prior to being placed in position to seal the refrigerator.

The body of the refrigerator shown in the drawings has an outer metal shell l2, the panels of which are adapted to be fabricated on a metal break or breaker press, and which encloses an inner metal liner member 14 forming a cold storage chamber. Any suitable or desirable insulating material [6 may be disposed between the liner l4 and the shell l2. In order to form a supporting connection between the liner and the shell which will not permit transfer of heat to the liner, a breaker strip 18, which extends around the outside of the upper edge of the liner is connected between the liner and the shell. The material of the breaker strip must be a poor conductor of heat and at the same time must have sufficient strength to serve as a support for the liner, Masonite or an equivalent material being satisfactory for this purpose.

The manner in which the breaker strip is connected to the liner and to the shell can best be seen in Fig. 8. The inner edge of the breaker strip is secured to a flange 20 of the liner and to one side of an angle 22, the other side of the angle being secured to the vertical wall of the liner. The outer edge of the breaker strip is secured to one edge of a metal connecting member 24 which is in turn welded to an inwardly ex-. tending flange of the shell l2.

The top of the refrigerator is constructed according to the same principles as the refrigerator body. An outer metallic covering 26, provided with a plurality of openings to accommodate removable lids 28, is connected to an inner metallic lining 30, having aligned openings. by means of an insulating breaker strip 32 extending around the outer edge of the metallic liner 30. Suitable insulating material 34 is placed between the covering 26 and liner 30. Around the edges of the openings which accommodate the lids 28, hard rubber frames 36 are provided which are connected at the upper end to a downwardly extending flange on the covering and at the lower end to an upwardly extending flange on the liner 30. The lids 28 are also formed of a nonheat conducting material, such as hard rubber.

.The top of the refrigerator is supported and maintained in position by means of metallic angles 38, one side of which is secured to the liner 30 and to the inner edge of breaker strip 32 by bolts 39, and the other side of which is secured to the vertical wall of the liner I l.

A hollow rubber gasket 40 is compressed between the upper edge of liner M and liner 30 to In addition, insulating material (I is The shell I! is so formed as to provide a compartment 4! below the refrigerator at one side thereof. This compartment houses the compressor ll and condenser III of a hermetically sealed primary refrigerant circulating system. The prlmary system also includes an L-shaped evaporator coil 52 which is placed inside the cold storage compartment formed by liner It. A capillary tube it connects the outlet side of the condenser III to the evaporator coil 52, and a return conduit It connects the evaporator coil to'the inlet side of the compressor 48.

The entire primary system, including the compressor 48, the condenser II and the evaporator I2, together with the conduits which connect them, is intended to be removable from the refrigerator for servicing. The'unit is serviced at a central service point or stop where little or no difficulty is involved in handling the draining the edge of the liner II. Furthermore, the interior-of the closure element I. may be packed with insulating material.

. Wrapped around the outside of theliner i4 is the tubing which constitutes thesecondary re- Y frigerant circulating system It. The coil 82 of the secondary system which is maintained in and recharging of the system necessary if parts are removed for replacement or repair. During the interim when the primary system. is being serviced, another such system may be installed.

The primary evaporator coil or is mounted on an L-shaped metal supporting plate 58,-which is attached by means of screws '80 to blocks "which are dried to the liner II. The coils of the evaporator 52 are thus maintained in heat exchange relation with the liner ll. As shown in Fig. l, the evaporator coils lie along one side of the liner l4 and along a shelf 64 formed by the liner above the compressor and condenser compartment 46. The chamber formed above plate 58, which is supported by the shelf 64, has a particularly low temperature due to the primary circuit evaporator and servesas a quick-freezing compartment.

The capillary tube 54 and the return conduit 58 are shown extending upward inside a stack which directs the flow of cooling air across the 'condenser. In order that the tube 54 and con duit I! may have an entryway into the cold storage chamber, an opening 11, shown in Fig. 4, having insulating walls 15, is provided in the top portion of the refrigerator. tube-supporting blocks II and 88 (see Fig. 7) are A pair of removable positioned at the outer and inner sides of the opening, respectively. and are provided with holes Ill and 12 therein for accommodating the tube It and the return conduit 56, respectively. The re- 1 movable supporting blocks is and 69 may be slit between the openings IO-and I2 and the edges of the blocks, in order that the conduit and tube may be placed in the openings. Rubber, which is flexible, and also a non-conductor of heat, will serve satisfactorily as the material of the blocks 68 and 69. Openings 14 are provided in the blocks to accommodate a tube 16 which constitutes a part 01' the thermostatic control of the refrigerator. One end of the tube extends inside i the cold storage compartment inorder to be responsive to temperature conditions therein, while the other end of the tube may control a switch which controls the operation of the compressor. Thus, expansion and contraction of a gas in the tube so control a thermostatic element that the compressor will be turned oif and on whenever necessary to maintain a substantially even temperature in the cold storage compartment.

heat transfer relationship with the shelf 84 constitutes the condenser portion'of the secondary system. The remainder of the secondary tubing which forms a coil in heat exchange relationship with the sides and bottom of the main portion at of liner it constitutes the evaporator portion of the system, and serves' to maintain the large storage compartment at the desired low temperature. The arrangement of the secondary circuit is such that circulation of the refrigerant is constant, and no circulating pump is required. The secondarycircuit, it will be noticed, is assembled in relatively permanent relationship with the body of the refrigerator and is not intended to .be disturbed when the primary circuit is removed for servicing.

- When it is necessary to service the primary cir-- cult, the lid 20 and closure element 18 are first removed. Then the screws which hold the plate 58 are loosened, and the entire evaporating unit of the primary circuit maybe lifted out of the cold compartment, carrying with it the two rubber. spacing blocks IQ and N. If the width ofclaims to said embodiment, but to include all de-.

vices embodying substantially the same or equivalent means to accomplish the same or substantially equivalent results.

I claim:

1. A refrigeration unit comprising an interior liner forming a cold compartment, means exte'rior to said liner for insulating it from outside thermal conditions, an evaporator coil removably mounted within the cold compartment in heat exchange contact with the interior of said liner, an integral removable primary refrigerating unit of the hermetic type including a compressor and condenser connected in series with the evaporator coil, and a secondary coil mounted exteriorly of the liner and cooled by the primary evaporator coil, said secondary coil being wound freely about the liner, whereby a portion of the cold compartment is cooled primarily by the first-mentioned evaporator coil and the remainder of the cold compartment is cooled primarily by the secfreezing section is cooled primarily by the flrstmentioned evaporator coil and the remainder of the cold compartment is cooled primarily by the secondary coil.

3. A refrigeration unit comprising an interior liner forming a cold compartment, means exterior to said liner for insulating it from outside thermal conditions, an evaporator coil removably mounted on a section of the interior of said liner, an integral removable primary refrigerating unit of the hermetic type including a compressor and condenser connected in series with the evaporator coil, and a secondary coil mounted exteriorly of the liner and cooled by conduction of heat through the liner to the primary evaporator coil, said secondary coil being wound freely about the liner, whereby a portion of the cold compartment is cooled primarily by the first-mentioned evaporator coil and the remainder of the cold compartment is cooled primarily by the secondary coil.

4. A refrigerator having a food storage compartment formed by a metallic liner, a primary refrigerant circulating system having an evaporator mounted inside said liner and in heat exchange relation therewith, a secondary refrigerant circulating system in heat exchange relation with the exterior of said liner comprising a condenser portion opposite the primary system evaporator, and an evaporator portion in heat exchange relation with the liner remote from said primary system evaporator.

5. A refrigerator comprising a body portion, an insulated liner inside said body portion forming a cold compartment, an evaporator coil removably mounted on a section of the interior of said liner, 9, cover portion for said refrigerator having an opening therein through which the connections of the evaporator coil extend, an integral removable primary refrigerating unit of the hermetic type including a compressor and condenser connected in series with the evaporator coil, removable means for positioning the connections of said primary evaporator coil and closing said opening in the refrigerator cover, and a secondary coil mounted exteriorly of the liner and in heat transfer relation with the primary evaporator coil through the wall of the liner, said secondary coil being wound freely around the liner, whereby a portion of the cold compartment is cooled primarily by the first-mentioned evaporator coil and the remainder of the cold compartment is cooled primarily by the secondary coil.

6. A refrigerator comprising a body portion, an insulated liner inside said body portion forming a cold compartment, a primary evaporator coil positioned in one section of the interior of said liner and in heat exchange relationship therewith, means detachably securing said evaporator coil to said liner, a cover portion for the refrigerator having an opening therein through which the connections of said evaporator coil extend, an integral removable primary refrigerating unit including a compressor and condenser connected in series with said evaporator coil, removable means for positioning said connections of said evaporator coil and closing said opening in said refrigerator cover, and a secondary coil mounted exteriorly of said liner and in heat transfer relation with said primary evaporator coil through the wall of said liner, said secondary coil having a condenser portion opposite said primary evaporator coil and an evaporator portion around those portions of said liner not contacted by sai primary evaporator coil.

'7. A refrigeration unit comprising a single interior liner forming a cold compartment, said liner being shaped with a shelf to define a fast freezing section in said compartment, means exterior to said liner for insulating it from outside thermal conditions, a primary evaporator coil removably mounted on the interior ofsaid liner in said fast freezing section, said primary evaporator coil being in heat exchange relationship with said liner, an integral removable primary refrigerating unit of the hermetic type including a compressor and condenser connected in series with said primary evaporator coil, and a o ary evaporator coil mounted exteriorly of the liner and having a condenser portion cooled by said primary evaporator coil through said liner, and an evaporator portion wound freely about said liner, whereby said fast freezing section -is cooled primarily by said primary evaporator coil and the remainder of said cold compartment is cooled primarily by said secondary coil.

8. A refrigerator comprising in combination a body portion having generally vertically disposed heat insulated walls, a heat insulated cover portion mounted on said walls and provided with an access opening therein, said walls and said cover portion forming a, food storage compartment, a refrigerant circulating system having an evaporator portion within said food storage compartment, tubes connected to the inlet and to the outlet of said evaporator portion and leading to a point exterior of said body portion, an opening formed in said cover portion through which said tubes extend, heat insulating resilient means holding said tubes in said opening, and a closure for said openin concealing said tubes and cooperating with said heat insulating resilient means to provide a seal for said opening.

9. A refrigerator comprising in combination a body portion having generally vertically disposed heat insulated walls, a heat insulated cover portion mounted on said walls and provided with an access opening therein, said walls and said cover portion forming a food storage compartment, a refrigerant circulating system having an evaporator portion within said food storage compartment, tubes connected to the inlet and to the outlet of said evaporator portion and leading to a point exterior of said body portion, an opening formed in said cover portion through which said tubes extend, a pair of rubber-like blocks encircling said tubes and removably secured in said opening, and a closure for said opening concealing said tubes and cooperating with said blocks to provide a seal for said opening.

10. A refrigerator comprising in combination a body portion having generally vertically disposed heat insulated walls, a heat insulated cover portion mounted on said walls and provided with an access opening therein, said walls and said cover portion forming a food storage compartment, a refrigerant circulating system having an evaporator portion within said food storage compartment,.tubes connected to the inlet and to the outlet of said evaporator portion and leading toa 7 point exterior 012- said body portion. an opening through one side of said cover portion through which=said tubes extend, heat insulating resilient means holding said tubes in said opening,

and a closure for said opening concealing said tubes, said closure cooperating with said heat insulated resilient means and with the walls of said opening concealing said tubes, said closure coopening to form a thermal insulating space around said tubes to seal said food storage compartment from the atmosphere. n

11. A refrigerator comprising in combination a body portion having generally vertically disposed heat insulated walls, a heat insulated cover portion mounted on said walls and provided with an access opening therein, said walls and said cover portion forming a food storage compartment, a'

refrigerant circulating system having an evaporator portion within said food storage compartment, tubes connected to the inlet and to the outlet of said evaporator portion and leading to a point exterior of said bcdy portion, an opening through one side of said cover portion through operating with said blocks and with the walls of said opening to term a thermal insulating space around said tubes to seal said food storage compartment from the atmosphere.

, GEORGE K. IWABHITA.

REFERENCES CITED The'foliowing references are of record in the file of this patent:

UNITED STATE") PATENTS- Number Name Date 2,084,494 Hull June 22, 1937 2,246,551 Stickel Junev 4, 1941 Steenstrup Dec. '1, 1937 

